Light weight pallet construction

ABSTRACT

A reversible, compact stacking, fork-lift type pallet consisting of a sheet of rigid material having spaced, parallel, diagonally disposed folds to provide a corrugated structure having four sides. Rows of aligned openings extend through adjacent folds to receive the usual spaced tines of a fork-lift truck from multiple directions. In manufacture a single sheet of material in the shape of a rhomboid parallelogram is perforated and then folded to the required corrugated shape.

United States Patent Drelicharz [54] LIGHT WEIGHT PALLET CONSTRUCTION [72] Inventor: Joseph A. Drelicharz, Oxnard, Calif.

[73] Assignee: The United States of America as represented by the Secretary of the Navy 22 Filed: Jan.20, 1971 21 Appl.No.: 107,922

[52] US. Cl. ..108/53, 108/58, 161/133 [51] Int. Cl. ..B65d-19/04 [58] Field of Search ,.l08/5l-58; 220/72;

[56] References Cited UNITED STATES PATENTS 520,366 5/1894 Leaver ..161/136 3,610,173 10/1971 Mcllwraith et al. ..108/57 3,187,691 6/1965 Leitzel ..108/58 2,544,743 3/1951 Vrabcak ..l08/58 X 3,256,806 6/1966 Jordan ..220 72 1451 De c. 5, 1972 3,591,032 Baxter ..108/53 3,037,592 6 1962 Shipley et al. ..161/136 x 1,948,986 2/1934 .laquith ..217/26 FOREIGN PATENTS OR APPLICATIONS 931,539 7/1963 Great Britain 108/58 1,570,229 6/1969 France ..220/72 Primary Examiner--Bobby R. Gay

Assistant Examiner-Peter A. Aschenbrenner Attorney-Richard S. Sciascia, Q. Baxter Warner and Gayward N. Mann [5 7] ABSTRACT A reversible, compact stacking, fork-lift type pallet consisting of a sheet of rigid material, having spaced, parallel, diagonally disposed folds to provide a corrugated structure having four sides. Rows of aligned openings extend through adjacent folds to receive the usual spaced tines of a fork-lift truck from multiple directions. In manufacture a single sheet of material in the shape of a rhomboid parallelogram is perforated and then folded to the required corrugated shape.

4 Claims, 7 Drawing Figures LIGHT WEIGHT PALLET CONSTRUCTION STATEMENT OF GOVERNMENT INTEREST BACKGROUND OF THE INVENTION 1. Field of the Invention This invention. relates to pallets and more particularly to cargo pallets capable of supporting and transporting cargo in conjunction with the conventional fork-type lift truck.

2. Description of the Prior Art A customary way of transporting cargo is by stacking the cargo on a pallet and then moving the pallet and supported cargo to a desired area. While this method has been extensively used in the past, the pallets employed have not been completely satisfactory due primarily to excessive weight, inadequate strength, and inability to nest together for compact storage when empty.

Furthermore, prior art pallets have been found inadequate to improve the material handling rates at the terminal ends of the ship-to-shore cycle to complement the high speed of ships being developed as part of the Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings wherein:

. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a pallet constructed in accordance with the present invention. 7

FIG. 2 is a stop plan view of a pallet blank prior to being folded.

FIG. 3 is a top plan view of a finished pallet showing diagonal fold lines and rows of openings enabling lift truck tine insertion from all four sides.

FIG. 4 is a side elevational view taken along line 44 of FIG. 3.

FIG. 5 is an end elevational view taken along line 5- 5 of FIG. 3. v

FIG. 6 is a detail cross sectional view of a modified fold shape. i j

FIG. 7 is a side elevational view of a large pallet shown stacked with four smaller pallets thereon.

growing Navy amphibious assault landing craft pro- I gram.

SUMMARY OF THE INVENTION The present invention comprises a fork lift type pallet constructed of a sheet of rigid material having diagonally disposed folds or corrugations. Rows of aligned openings are provided to enable insertion of the tines of a fork lift truck from any side which greatly simplifies many problems in handling pallets in confined areas.

The present invention is a satisfactory way of increasing cargo transfer rates, because in one employment a single, relatively large pallet may be utilized for supporting and transporting smaller cargo bearing pallets which are later removed and used in handling such cargo in confined storage areas.

STATEMENT OF THE OBJECTS OF THE INVENTION It is an object of the present invention to provide a cargo supporting pallet of novel design which lends itself of both cable sling and fork lift truck manipulation.

Another object of the present invention is to provide strong but relatively light cargo pallets which, when empty nest together compactly and readily lend themselves to high density stacking and hence small dimensions for return of empties.

Still another object is to provide a strong cargo pallet which is simple to fabricate of sheet material, economical in manufacturing and maintenance cost and, in at least one form, disposable after only one use thereof.

Another object is to provide a single piece cargo pallet with reinforced sides to provide additional strength and stiffness.

Still another object of the invention is to provides a cargo pallet of minimum overall thickness or height and which may be loaded on wither side and hence need never be turned over before use.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, this invention in general comprises a pallet 10 of the type commonly handled with fork-lift truck equipment but made from a single sheet or plate of rigid material 12 (FIG. 2) folded to produce diagonally disposed parallel corrugations or folds l4. Rows of spaced aligned openings 16 and 17 are provided in the folds as shown in FIG. 3 to enable insertion of the lifting tines of a conventional fork-lift truck from multiple directions. The sheet 12 is preferably of a relatively thin but strong sheet material which can readily be folded or corrugated. This sheet may also be of a malleable material or a material which is capable of being molded or cast and need not necessarily be of metal.

In the fabrication of pallet 10, the sheet 12 may first be cut to the desired shape, such as the rhomboid shown in FIG. 2, and the rows of aligned openings 16 and 17 may then be cut, punched or otherwise formed therein. The general shape, size and placement of the openings are dependent on the size of the lift-fork tines and the strength characteristics required. The next operation is to pass the perforated sheet 12 through a press or sheet metal brake to form the folds or corrugations. Tie down receiving openings or grab eyes 18 may also be provided where desired. Their purpose is to engage tie down ends for the cargo so that a strong connection between cargo and pallet is assured. These openings may be provided with similarly apertured back-up or reinforcement plates 19 if desired as shown in FIG. 3. which may be welded or otherwise secured in place. The inverted keyhole shape of the grab eyes is most convenient since the large portion is of sufficient size to admit the end of a link chain while the narrow slot may then receive a selected chain link to assure a tight fit of the cargo tethering hold down strap.

It is to be noted that in the event a square or rectangular shape of the finished pallet 10 is desired, a rhombus or rhomboid shaped blank 12 respectively is employed.

As the folds 14 are formed, the overall dimensions and shape of the blank change until the desired coneffecting the folds in sheet 12 may be employed whether it be by folding, molding, welding or casting, depending on the materiaLSimilarly the depth, fold angle with respect to the plan and cross-section, position and type of tie down openings, etc., are dictated by the desired strength and size characteristics. As shown in FIG. '6 the fold 14 need not present a sharp. angular.

upper face as shown in FIG. 1. Instead the fold 14 may be of a more rounded configuration 20 (FIG. 6) which will provide a greater load bearing area in contact with the load and hence assist in preventing possible damage to cargo carried thereon. The pallet 10 in its basic form may be somewhat flexible; however, additional strength and stiffness will be imparted if the sides are gussetted with triangular plates. Note the triangular shaped gusset projections 22 in FIG. 2 which when sheet 12 has been folded, may be turned down and welded in place to form angular shaped members which add increased strength to the pallet. Such gussets 22 may be provided on adjacent sides of the pallet and in such manner as not to interfere with pallet nesting capabilities. For illustrative purposes arrows 21 and 23 have been shown-in FIG. 2 to indicate the direction of fold of gussets 22. When so folded the contacting edge portions may be welded or otherwise secured in place. Of course the gussets on two adjacent sides are folded downwardly and those on the other two adjacent sides are folded upwardly in order to prevent interference with the nesting properties of the pallet.- During such nesting the superimposed pallet is shifted slightly to one side in order to clear the gussets of the pallet below.

In addition to the gussets described above a marginal reinforcement 24 may be added as shown in FIG. 1. This may be in the form of descrete pieces as shown or a may be a continuous strip of reinforcing material along the bottom or top edges of two adjacent sides so as not to interfere with nested stacking.

In FIG. 7 an assembly of several pallets is diagrammatically depicted. As shown several regulation size pallets l constructed in accordance with the present invention or otherwise are mounted upon a larger size pallet A which may also be constructed in accordance with the present invention. Suitable hold down straps are employed to keep individual loads upon the smaller pallets and similar straps may be used to hold the smaller pallets and loads to the large pallet. Such arrangement has an important advantage for ship loading and unloading operations in that the assembly may be stowed as a unit during warehouse storage, dockside handling, and shore to ship transport but may readily be broken up into smaller units for manipulation below decks with a ship. During ship-to-shore operations the reverse occurs.

It will be noted that the keyhole shaped tie down receiving openings or grab eyes 18 may be used as fastening means not only for the ends of cargo tethering leashes to secure the cargo load to a pallet, but also to receive the ends of crane lines or bridles using a four point hookup with an appropriate spreader bar. By this means a large pallet supporting four smaller pallets, each bearing its separate load, can be hoisted aloft and lowered into a ships hold to be later split up and the smaller pallets manipulated into confined areas by fork lift truck, etc.

As an example of pallet size, four standard warehouse pallets (40 X 48 inches) with a total load capacity of 10,000 lbs, have been satisfactorily handled by a large pallet of approximately 8 X 9 feet size when the latter is constructed of one-eighth inch steel plate formed in accordance with the present invention. In such instance the tare weight of the large pallet was l,200 lbs. However, it could be much less if constructed of lighter metal such as aluminum. In manipulating the large pallet just described it has been found practical to employ a fork lift truck having tines inches long, 10 inches wide, 3 inches deep and 48 inches on centers.

Of particular value is the ability of the pallet of the present invention to flex or give when subjected to sudden deceleration while being lowered by a sling. This aids in preventing cable breakage or-pallet collapse during ship to shore handling, etc.,' by crane, and adds to the pallets life expectancy.

Of course the fold number, position and angleof fold can be optimized, as may also be the radii of the fold crease.

It will be noted that no time need be lost in discriminating top from bottom, since the opposite sides of the pallet are identical and either side may serve as the cargo supporting surface.

Obviously many modifications and variations of the present invention are possible oriented the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

I claim:

I. A fork-lift type pallet constructed to permit lift truck fork entry thereinto from all four sides comprismg:

a substantially single flat sheet of rigid material, said sheet being formed to provide a series of spaced, parallel corrugations extending diagonally thereacross, to form a load bearing surface including a series of spaced alternate ridges and valleys,

the folds of said corrugated portion being perforated with spaced openings oriented in alignment to receive the spaced tines of a fork-lift truck therethrough;

said folds also having a second series of spaced openings extending in a direction substantially perpendicular to the first series and also adapted to receive the spaced tines of a fork-lift truck therethrough;

said corrugations and resulting ridges and depressions being similarly spaced so that when several pallets are stacked they lie in nested relationship with the ridge portions of one registering with and nested into the valley portions of the other, whereby a multiple entry pallet is provided which has sufficient thickness to receive fork lift truck tines but may readily be stacked in nested relation ship to conserve vertical space during storage.

2. A reversible pallet construction formed of a single sheet of planar material, said sheet having been initially in the rhomboidal shape and being diagonally folded to reduce the overall size and change the outline shape of said sheet until such shape is rectangular in configuration, said folds being in the form of corrugations of similar size and shape so that superimposed pallets may compactly nest together;

each of said diagonal folds being perforated to receive the tines of a fork-lift truck, said perforations being placed in line to permit a tine to pass through aligned openings in a number of corrugations and said openings being arranged in spaced relationship to register with the spaced tines of the fork-lift truck,

and a second series of openings aligned in a direction perpendicular to the first and also adapted to 

1. A fork-lift type pallet constructed to permit lift truck fork entry thereinto from all four sides comprising: a substantially single flat sheet of rigid material, said sheet being formed to provide a series of spaced, parallel corrugations extending diagonally thereacross, to form a load bearing surface including a series of spaced alternate ridges and valleys, the folds of said corrugated portion being perforated with spaced openings oriented in alignment to receive the spaced tines of a fork-lift truck therethrough; said folds also having a second series of spaced openings extending in a direction substantially perpendicular to the first series and also adapted to receive the spaced tines of a fork-lift truck therethrough; said corrugations and resulting ridges and depressions being similarly spaced so that when several pallets are stacked they lie in nested relationship with the ridge portions of one registering with and nested into the valley portions of the other, whereby a multiple entry pallet is provided which has sufficient thickness to receive fork lift truck tines but may readily be stacked in nested relationship to conserve vertical space during storage.
 2. A reversible pallet construction formed of a single sheet of planar material, said sheet having been initially in the rhomboidal shape and being diagonally folded to reduce the overall size and change the outline shape of said sheet until such shape is rectangular in configuration, said folds being in the form of corrugations of similar size and shape so that superimposed pallets may compactly nest together; each of said diagonal folds being perforated to receive the tines of a fork-lift truck, said perforations being placed in line to permit a tine to pass through aligned openings in a number of corrugations and said openings being arranged in spaced relationship to register with the spaced tines of the fork-lift truck, and a second series of openings aligned in a direction perpendicular to the first and also adapted to receive the spaced tines of a fork-lift truck therethrough to provide a stackable pallet of planar construction having four-way entry for the tines of a fork-lift truck.
 3. The pallet construction as defined in claim 2 wherein said folds are of rounded configuration to provide an increased load bearing area.
 4. The pallet construction as defined in claim 2 wherein reinforcing members are added to the sides of said pallet to add increased strength thereto. 